So why aren’t we using it?

While some are focused on how to harvest energy from waves, others are looking at how to extract the ocean’s vast reserves of naturally occurring uranium and turn it into fuel.

A research team at Stanford is currently working to improve on a uranium-extraction process pioneered by Japan in the 90s. The process involves dipping negatively charged plastic fibers into seawater; the negative charge of the fibers attracts positively charged uranyl ions. (Uranyl is uranium attached to oxygen, so scientists must chemically treat the fibers to separate the oxygen from the pure uranium.)

Until recently, the only way to get uranium was to dig it out of the ground. | Fox Photos/Getty

The team at Stanford hasn’t developed a way to make this process cost effective yet, but if they can, the benefits will be huge. There’s currently 4 billion tons of uranium floating in the Earth’s seas. That’s enough, some say, to power the planet for the next 13,000 years.

The problem, though, is that the ocean is enormous. As Seeker points out, there are 1.3 sextillion liters of water in the ocean. Fully spelled out, that number looks like this: 1,300,000,000,000,000,000,000. Yep, that’s 20 zeroes.

Because the ocean’s uranium saturation is so sparse — picture a single grain of salt dissolved in a liter of water and you’ll start to get the idea — scientists need to seriously increase the efficiency of uranium extraction if they hope to turn this into an economically feasible process.

If they can, though, we’ll have a natural source of energy that’s literally inexhaustible. And that’s a goal worth striving for.